The present invention generally relates to agricultural equipment, and more particularly to a spraying apparatus for spraying agricultural chemicals on shrubby and/or small size arboreous crops or other types of plants during the early stages of their growth when the plants are disposed in lines or arrays with empty areas between them.
It is widely known to spray shrubbery and/or small size arboreous trees, or even bigger trees in the early stages of their growth with a spraying apparatus which may or may not be provided with means for detecting the presence of a plant in the area to be sprayed. The known spraying apparatuses are usually adjusted to the plants to be sprayed. This procedure, however, brings about a number of drawbacks, starting with the inadequate dimension of the machines which therefore spray volumes of agricultural chemicals much greater than necessary. As a result, when a spraying apparatus is not provided with detecting means for detecting the presence of a plant in a spraying area, huge amounts of chemicals are wasted, resulting in loss of the chemicals and environmental pollution, since the chemicals are continuously sprayed even in the areas between the plants.
When the spraying apparatus is provided with a detecting means to spray the chemicals only when a tree is detected in a spraying target area, such machines are designed for use with grown up plants. The drawbacks of these machines are that they are not efficient due to the fact that the machines are positioned away from the plants as they pass along the center of the passages defined by the arrays of plants. Also, such machines provided with the detecting means usually have speed sensors in order to compensate for the distance between the detecting means and the spraying nozzles along the spraying apparatus. Thereby there is a high probability that the chemical can be wasted. Due to the small size of the shrubbery and/or arborous trees, it is possible that the delayed activation of the spraying nozzle in response to the detection of a tree in a spraying target area may happen before the tree has reached the target area or after it has already passed it. Thereby the chemicals will be sprayed into the air and not on the plant, and only a part of the chemical reaches the plant.
Another alternative which is used for spraying of shrubby and/or small size araborus trees is to manually spray the chemicals with spraying guns. However, this solution goes against the present tendency of mechanisiziation of agricultural works. In addition, it is a very difficult, dangerous and in some places forbidden process.